From 7937be5d14228870ca1266ac1ce2229b179b6e5b Mon Sep 17 00:00:00 2001
From: KRM7 <70973547+KRM7@users.noreply.github.com>
Date: Wed, 14 Aug 2024 19:41:43 +0200
Subject: [PATCH] use custom struct for CandidatePair instead of std::pair

---
 src/core/candidate.hpp    | 6 +++++-
 src/core/ga_base.impl.hpp | 6 +++---
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/core/candidate.hpp b/src/core/candidate.hpp
index dc63c08f..2ee3f458 100644
--- a/src/core/candidate.hpp
+++ b/src/core/candidate.hpp
@@ -135,7 +135,11 @@ namespace gapp
 
     /** A pair of candidates. */
     template<typename T>
-    using CandidatePair = std::pair<Candidate<T>, Candidate<T>>;
+    struct CandidatePair
+    {
+        Candidate<T> first;
+        Candidate<T> second;
+    };
 
 
     /**
diff --git a/src/core/ga_base.impl.hpp b/src/core/ga_base.impl.hpp
index 47d5e28b..5604a6f5 100644
--- a/src/core/ga_base.impl.hpp
+++ b/src/core/ga_base.impl.hpp
@@ -493,9 +493,9 @@ namespace gapp
         prepareSelections();
         detail::parallel_for(detail::iota_iterator(0_sz), detail::iota_iterator(population_size_ / 2), [&](size_t i)
         {
-            Candidate<T>& child1 = children[2 * i];
-            Candidate<T>& child2 = children[2 * i + 1];
-            std::tie(child1, child2) = crossover(select(), select());
+            CandidatePair child_pair = crossover(select(), select());
+            children[2 * i]     = std::move(child_pair.first);
+            children[2 * i + 1] = std::move(child_pair.second);
         });
 
         if (population_size_ % 2) children.back() = crossover(select(), select()).first;